Yes, like John O, I think this post misdiagnoses the problem.
John and Mary have beliefs about the evening star, not ‘the evening star’. Their beliefs are about the world, not about the words. Neither of them believes that ‘the evening star’ is the god Venus. Who ever thought that the god Venus was a string of three words!?
Further—though more contentiously—we might even deny that Mary has any beliefs about the evening star (that very thing, i.e. the planet). She takes the world to be a certain way, such that a god Venus appears in the evening sky, etc. But given that our term ‘the evening star’ actually denotes a planet, perhaps we misdescribe Mary’s belief by employing this term. She might attempt to use the term herself in describing her belief, but this is because she doesn’t really know what it means, so she doesn’t realize that linguistic error is causing her to misdescribe her belief contents.
But given that our term ‘the evening star’ actually denotes a planet, perhaps we misdescribe Mary’s belief by employing this term.
I believe that is exactly what Eliezer is saying.
“The evening star” refers to two entirely different things to Marry and John. John believes 2+2 = 4, while Marry believes 2+2 = red and 4 = blue. Attempting to substitute 4 for red does not work, because John’s 4 is not even the same type of thing as Mary’s.
John learns that Mary believes 2+2 = red. When John sees Marry write ((2+2) + 4) = purple, John incorrectly thinks Mary believes (red + red) = purple.
The problem, of course, is that Mary does not believe 2+2=4, to her that would be ridiculous, so John makes an incorrect inference about what Mary does believe because his beliefs are entirely different.
Yes, like John O, I think this post misdiagnoses the problem.
John and Mary have beliefs about the evening star, not ‘the evening star’. Their beliefs are about the world, not about the words. Neither of them believes that ‘the evening star’ is the god Venus. Who ever thought that the god Venus was a string of three words!?
Further—though more contentiously—we might even deny that Mary has any beliefs about the evening star (that very thing, i.e. the planet). She takes the world to be a certain way, such that a god Venus appears in the evening sky, etc. But given that our term ‘the evening star’ actually denotes a planet, perhaps we misdescribe Mary’s belief by employing this term. She might attempt to use the term herself in describing her belief, but this is because she doesn’t really know what it means, so she doesn’t realize that linguistic error is causing her to misdescribe her belief contents.
For further explanation, see: Belief Content and Linguistic Error.
I believe that is exactly what Eliezer is saying.
“The evening star” refers to two entirely different things to Marry and John. John believes 2+2 = 4, while Marry believes 2+2 = red and 4 = blue. Attempting to substitute 4 for red does not work, because John’s 4 is not even the same type of thing as Mary’s.
John learns that Mary believes 2+2 = red. When John sees Marry write ((2+2) + 4) = purple, John incorrectly thinks Mary believes (red + red) = purple.
The problem, of course, is that Mary does not believe 2+2=4, to her that would be ridiculous, so John makes an incorrect inference about what Mary does believe because his beliefs are entirely different.